You’re crafting all 16 slots on alts? You only need enchanted aspect crests (the 4x per Spark item) if you’re crafting. Otherwise, you only need 1 aspect crest per item to hit 441, which is the highest you can upgrade items – any higher have to come from Mythic raid (or last 2 Heroic bosses) or the vault.
That sounds like a 10.2 QoL change, after the introduce the S3 version of crests of course.
Remember from their original announcement, they told us already they would “wait several weeks” before making any changes to the system to evaluate the data.
Dunno why you feel the need to have an alt as geared as your main. It’s already easy enough to get 441 in 3 weeks. Alts should be alts not mains. If you want to characters at full BiS should require some work it’s already made easier for alts what you want instant BiS gear? Just cus your main got the gear?